1. Field of the Invention
This invention relates generally to an aperture correction circuit, and more particularly to an aperture correction circuit by which ideal corrected video signals having sharp edged waveforms are obtained.
2. Description of the Prior Art
In television receivers or the like, the sharpness of a reproduced picture is limited by the frequency and phase response of the video channels of the receivers and by the size of the beam spot on its cathode ray tube.
In order to improve the picture sharpness, so-called aperture correction circuits are provided which are well known in the prior art.
Conventional aperture correction circuits of the prior art perform their operations by superimposing twice-differentiated signals of input video signals on the input video signals.
However, in actual television receivers and the like, the input video signals have relatively dull edged waveforms so that correcting signals having sharp waveforms can't be obtained just by differentiating the input video signals. That is, the input video signals can't be corrected sufficiently.